No reading at diag port
#1
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Car: 67 ******mobile
Engine: 385 Solid roller
Transmission: T-56
Axle/Gears: 4.11
No reading at diag port
Hope this is in the right section
Not getting info on another board I need hope its ok
1990 C4 similar OBD 1 computer as you guys'
Went to put an innova8 code reader on it the port is dead, nothing.
Its brand new and works fine tried it on my truck
Tried shorting a and b, nothing.
car starts and runs just no juice there.
What to check, where to go?
Lost on this one Im not good with this but tired of seeing a friend get ripped off at shops. Its my old Z so kind of like to see it get tightened back up so to speak
Not getting info on another board I need hope its ok
1990 C4 similar OBD 1 computer as you guys'
Went to put an innova8 code reader on it the port is dead, nothing.
Its brand new and works fine tried it on my truck
Tried shorting a and b, nothing.
car starts and runs just no juice there.
What to check, where to go?
Lost on this one Im not good with this but tired of seeing a friend get ripped off at shops. Its my old Z so kind of like to see it get tightened back up so to speak
#2
Re: No reading at diag port
I am having this problem too with my 89 Formula 350. CEL is on, but when scan tool is hooked up, scan tool does not report any codes. Yet, CEL goes on every time. Car runs and drives perfect thus far.
#3
Re: No reading at diag port
A is a just ground, b is the lead to the 1227727 ecm to put the ecm in diagnostic mode when grounded pin b3 white with a black stripe. B1 is the mil/ check engine light out of the ecm the ground side. you should check out your grounds for the ecm and you mil bulb or even back probe with a test light at the ecm as a mill with pin b3 grounded . if still no field service mode the ecm is bad.
#4
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Car: 67 ******mobile
Engine: 385 Solid roller
Transmission: T-56
Axle/Gears: 4.11
Re: No reading at diag port
Thanks will check that out.
Was also told to look for a bad fuse could be on the lighter circuit ?....its never been used.
Wont be near the car for another week but Ill report back on the fix.
Was also told to look for a bad fuse could be on the lighter circuit ?....its never been used.
Wont be near the car for another week but Ill report back on the fix.
#5
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Car: 91' Firebird SOLD
Engine: 350 TPI +bolt-ons
Transmission: 700r4
Axle/Gears: 3:42
Re: No reading at diag port
I know that on the 7730 ecm (1990-92) Tpi. You have to have closer to 5v on The orange wire (Pin M) at the ALDL connector. If not ecm is probably bad.
#6
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Transmission: automatic
Re: No reading at diag port
I have a 1997 V6 Firebird. started having some hesitation problems and when given gas it seems as though it dont want to go. Also it smells funny via exhaust. Took it to repair shop and they can not get a diagnostic reading. starts up fine. was running great. any help please can not afford dealer
#7
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Transmission: automatic
Re: No reading at diag port
I have a 1997 V6 Firebirde that does not get a diagnostic reading. starts up fine, but does not get much power wont go over 20 miles an hour. exhaust has funny odor also. My mechanic can not figure it out.
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#8
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Transmission: automatic
Re: No reading at diag port
can not get a diagnostic ready for a 1997 V6 Fire-bird. start up fine rough idle and exhaust smells . 170,000 mileage . can anyone help?
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